POS1340 BASELINE CLINICAL DISEASE ACTIVITY IS NOT CRITICAL FOR PREDICTING REMISSION OF ADULTS ONSET STILL´S DISEASE
Authors: J. Groetsch, K. Tascilar, G. Schett, D. Foell, J. Rech
Journal: Annals of the Rheumatic Diseases (2022)

Background The clinical course of adult-onset Still’s disease (AoSD) is highly variable, ranging from subtle constitutional symptoms to life-threatening complications such as macrophage activation syndrome. Therefore, it is of interest whether baseline disease activity in AoSD predicts the clinical course, i.e. clinical and serological remission. Objectives The aim of this study was to compare whether two instruments to measure AoSD disease activity, Pouchot-Score and Still-Activity-Score (SAS), at baseline predict later remission of disease. We also assessed whether serum levels of calprotectin (S100A8/A9) are associated with clinical disease activity as measured by SAS at follow up. Methods AoSD was diagnosed according to the Yamaguchi criteria. In all patients Pouchot-Score and Still-Activity Score (SAS) were assessed at baseline and SAS score also at follow-up. Clinical remission was defined as absence of all AoSD symptoms (i.e. fever and arthralgia), while serological remission was defined as normalization of Ferritin, IL-18 and S100A8/A9 (calprotectin) levels. To investigate the prediction accuracy of the baseline Pouchot-Score and SAS for clinical and serological remission, a calculation of the areas under the receiver operating characteristic (ROC) curves was performed. Results 42 AoSD patients (19 males/23 females; mean+/-SD age:41+/-17 years) were assessed. Baseline Pouchot-Score was 5.3 +/- 1.6, baseline SAS was 5.7 +/- 1.0. With treatment of AoSD, clinical disease activity decreased reaching a mean SAS of 2.2 +/- 1.8 after a mean follow up time of 48 +/- 90 months. Glucocorticoids were used by 33%, methotrexate by 21%, IL-1 inhibitors by 33% and IL-6 inhibitors by 29% of the patients. 62% (N=26) of the 42 patients obtained clinical remission and 36% (N=15) serological remission. Neither Pouchot-Score (0.57) nor SAS (0.51) at baseline predicted clinical remission of AoSD. Furthermore, also serological remission was not predicted by baseline SAS (0.62) or Pouchot-Score (0.56) (Figure 1). With respect to activity of AoSD during treatment serum calprotectin levels were closely associated with SAS disease activity (r = 0.54, p &lt; 0.0003) (Figure 2). Conclusion Baseline AoSD disease activity as measured by Pouchot-Score and SAS does not predict clinical or serological remission. Serum calprotectin level is closely related to AoSD disease activity during the treatment phase. Figure 1. ROC for baseline SAS and Pouchot-Score and clinical remission Figure 2. Association between S100A8/A9 protein measured by the ELISA method and disease activity by the SAS at follow-up Acknowledgements The research project was supported by SOBI and Novartis. Disclosure of Interests Jennifer Groetsch: None declared, Koray Tascilar: None declared, Georg Schett: None declared, Dirk Foell: None declared, Jürgen Rech Speakers bureau: Abbvie, Biogen, BMS, Chugai, GSK, Lilly, MSD; Novartis, Roche, Sanofi, Sobi, UCB, Consultant of: Abbvie, Biogen, BMS, Chugai, GSK, Lilly, MSD, Novartis, Roche, Sanofi, Sobi, UCB, Grant/research support from: Sobi, Novartis